Hertha brushed aside their city rivals thanks to second-half goals from Vedad Ibisevic, Dodi Lukebakio, Matheus Cunha and Dedryck Boyata to follow up Saturday's 3-0 win at Hoffenheim when the league restarted after two months of inactivity due to the COVID-19 pandemic.
Played behind closed doors, the result lifted Hertha one place up to 10th on 34 points from 27 games while promoted Union, who won the reverse fixture in November 1-0 thanks to a late penalty, stayed 12th on 30 points.
In Saturday's standout fixtures, champions and league leaders Bayern Munich are at home to Eintracht Frankfurt while second-placed Borussia Dortmund visit Vfl Wolfsburg.
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(Writing by Zoran Milosavljevic; Editing by Toby Davis)
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